(19) |
 |
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(11) |
EP 0 399 675 A3 |
(12) |
EUROPEAN PATENT APPLICATION |
(88) |
Date of publication A3: |
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23.01.1991 Bulletin 1991/04 |
(43) |
Date of publication A2: |
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28.11.1990 Bulletin 1990/48 |
(22) |
Date of filing: 01.05.1990 |
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(84) |
Designated Contracting States: |
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BE DE FR GB IT NL |
(30) |
Priority: |
22.05.1989 US 354860
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(71) |
Applicant: Hewitt, J. Paul |
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Houston,
Texas 77079 (US) |
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(72) |
Inventor: |
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- Hewitt, J. Paul
Houston,
Texas 77079 (US)
|
(74) |
Representative: Cropp, John Anthony David et al |
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MATHYS & SQUIRE
100 Grays Inn Road London, WC1X 8AL London, WC1X 8AL (GB) |
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(54) |
Closed system refrigeration using a turboexpander |
(57) The present invention utilizes a turboexpander coupled with a compressor in place
of the Joules-Thomson expansion valve to achieve higher efficiency in a conventional
refrigeration used for removing condensable hydrocarbons or chemical vapors from air
which has been contaminated during loading and unloading at bulk plants. The more
efficient turboexpansion cycle allows the use of saturated lower aliphatic hydrocarbons,
such as ethane, as refrigerant, the use of which would be precluded from normal Joules-Thomson
expansion cycles. The turboexpander work is used to drive a compressor which partially
recompresses the expanded refrigerant gas, providing an essentially isentropic expansion.
Because the turboexpander and the compressor operate on the same fluid, the mass flows
through both are equal thereby alleviating control and loading problems.